Unsaturated sulfur-containing nematocides and fungicides

ABSTRACT

NEMATODES AND FUNGI ARE KILLED WITH A BIS(DICHLOROVINYL)SULFIDE, A BIS(TRICHLOROETHYL) SULFIDE OR A BIS(1,2, 2-TRICHLOROVINYL) SULFOXIDE.

United States Patent 3,790,683 UNSATURATED SULFUR-CONTAININ GNEMATOCIDES AND FUNGICIDES Paul C. Aichenegg, Prairie Village, Kans.,and Carl D. Emerson, Kansas City, Mo., assignors to Baychem Corporation,New York, N.Y.

No Drawing. Original application Jan. 27, 1964, Ser. No. 340,504, nowPatent No. 3,592,896. Divided and this application May 13, 1969, Ser.No. 824,275

Int. Cl. A01n 9/00 US. Cl. 424-337 8 Claims ABSTRACT OF THE DISCLOSURENematodes and fungi are killed with a bis(dichlorovinyl) sulfide, abis(trichloroethyl) sulfide or a bis(l,2, 2-trichlorovinyl) sulfoxide.

The present application is a division of application Ser. No. 340,504,filed Jan. 27, 1964 now Pat. 3,592,896.

This invention relates to new compounds, pesticidal uses of compoundsand new processes of making compounds.

Compounds which have good pre-emergent herbicide activity normally arenot satisfactory as nematocides since there remains the problem ofgrowing crops after the killing of the nematodes.

It is an object of the present invention to prepare nematocides whichare not good preemergent herbicides.

Another object is to prepare novel sulfides.

An additional object is to prepare novel unsaturated sulfoxides.

A further object is to prepare mixed saturated-unsaturated sulfoxidesand sulfides.

Yet another object is to devise a novel method for preparing puresulfides.

Still further objects and the entire scope of applicability of thepresent invention will become apparent from the detailed descriptiongiven hereinafter; it should be understood, however, that the detaileddescription and specific examples, while indicating preferredembodiments of the invention, are given by way of illustration only,since various changes and modifications within the spirit and scope ofthe invention will become apparent to those skilled in the art from thisdetailed description.

It has now been found that these objects can be attained by diversemeans as set forth below.

It may be noted that it is not predictable which sulfides and sulfoxideswill have good nematocidal and/or fungicidal activity. Thus, bis(1,2,2,2tetrachloroethyl) sulfoxide is ineffective as a nematocide. Similarly,bis(l,2,2, 2 tetrachloroethyl) sulfide is completely ineffective as anematocide and has poor fungicidal activity. Likewise, bis(l,2,2trichlorovinyl) sulfide shows no nematocidal activity and poorfungicidal activity. These compounds are not included in the presentinvention. However, somewhat similar compounds structurally, but withinthe invention, have good nematocidal activity and, in some cases, alsohave good fungicidal activity.

In one aspect of the invention there is prepared bis- (1,2,2trichloroethyl) sulfide. This compound is a much better parasiticnematocide and fungicide than the correspondingbis(2,2,2-trichloroethyl) sulfide.

In another aspect of the invention there are prepared unsaturatedsulfoxides of the formula where at least two of the Xs are halogen ofatomic weight between 35 and 80, i.e., chlorine or bromine, and

3,790,683. Patented Feb. 5, 1974 the other X is a halogen of atomicweight between 35 and or is hydrogen. It has been found that the bis-(2,2-dihalovinyl) sulfoxides are much poorer nematocides than either thebis(l,2 dihalovinyl) sulfoxides or the bis,1,2,2 trihalovinyl)sulfoxides. The bis(l,2,2-trihalovinyl) sulfoxides are poorer fungicidesthan the corresponding bis(l,2 dihalovinyl) sulfoxides. Illustrative ofsuch unsaturated sulfoxides are bis(l,2 dichlorovinyl) sulfoxide,bis(2,2 dichlorovinyl) sulfoxide, bis( 1,2,2- trichlorovinyl) sulfoxide,bis(l,2-dibromovinyl) sulfoxide.

It has been found that mixed trihaloethyldihalovinyl sulfides can beobtained by dehydrochlorination of bis- (trihaloethyl) sulfides in thepresence of tertiary amines, e.g., trimethyl amine, triethyl amine,tripropyl amine, triisopropyl amine, tributyl amine, trioctyl amine,pyridine, dimethyl aniline, dipropyl butyl amine, tribenzyl amine. Themixed polyhaloethyl-polyhalovinyl sulfide is obtained even if twice asmuch tertiary amine is used as is theoretically required for thereaction. On the other hand, when other alkaline agents are employed,e.g., alkali metal ethoxides such as sodium methoxide, sodium ethoxideand potassium butoxide, to dehydrochlorinate bis- (polyhaloethyl)sulfides there are obtained the expected bis(polyhalovinyl) sulfides.The polyhaloethyl polyhalovinyl sulfides and the bis(polyhalovinyl)sulfides can be converted to the correspoding sulfoxides by oxidation,e.g., with hydrogen peroxide or an organic peroxide. Examples of suchsulfides and sulfoxides not previously mentioned are 1,2,2trichloroethyl 1,2 dichlorovinyl sulfide, 1,2, 2 trichloroethyl 1,2dichlorovinyl sulfoxide, 1,2 di chlorovinyl sulfide,1,2,2-tribromoethyl-1,2-dibromovinyl sulfide.

The unsaturated sulfoxides can also be formed by directdehydrochlorination of the saturated sulfoxides, e.g., with sodiumalkoxide such as sodium ethoxide.

It is diflicult to prepare pure bis(polyhaloethyl) sulfides, e.g,,bis(l,2,2 trichloroethyl) sulfide or bis(2,2,2- trichloroethyl) sulfidedirectly since the normal procedure for preparing such compounds, e.g.,by reacting SCl with dichloroethylene results in a crudesulfide-disulfide mixture that is dilficult to separate. However, it hasbeen found that if the crude mixture is oxidized to form the sulfoxidethat the latter can be readily separated from the oxidation products ofthe disulfide. The sulfoxide in pure form can then be reduced, e.g.,with TiCl to form the pure bis(polyhaloethyl) sulfide.

Unless otherwise stated, all parts and percentages are by weight.

EXAMPLE 1 In 800 parts (8.0 moles) of symmetric cis dichloroferricchloride and 204 parts (2.0 moles) of sulfur dichloride were added at 30to 35 C. over a period of 3.0 hours. The product was allowed to standovernight and the ferric chloride removed by filtration. The materialwas washed with dilute aqueous hydrochloric acid and the organic layerdried and the solvent removed by stripping to give 383 parts of a crudemixture of bis- (1,2,2 trichloroethyl) sulfide and disulfide. Upondistillation in a high vacuum there was obtained 60.8 parts (22.2%yield) of pure bis(1,2,2-trichloroethyl) sulfide as a yellow oil B.P.102 to 108 C., n 1.5705.

This example was repeated several times using cis, trans or a mixture ofcis and trans dichloroethylene and reaction times from 2.5 to 3.0 hours.Removal of ferric chloride was also obtained by treatment twice with 1volume of acetone followed by dilution with 2 volumes of water followedby drying. The yields of crude mixtures ranged from 65 to 96% and theyield of pure bis(l,2,2-trichloroethyl) sulfide ranged from 22 to 28%.The pure compound is identified hereinafter as Compound 4975.

3 EXAMPLE 2 1 part of aluminum chloride was suspended in 50 parts (0.5mole) of cis-dichloroethylene and 20 parts (0.1 mole) of1,2,2-trichloroethyl sulfenyl chloride were added dropwise at 579 C.over a period of 15 minutes. Further heating of the mixture for 1 hourat 60 C. completed the reaction. The aluminum chloride catalyst wasremoved by treatment with 1 volume of acetone and then 2 volumes ofwater, the organic layer dried and then freed of solvent by vacuumstripping. 24.5 grams of crude addition product was obtained as a brownoil, 11 1.5770. Distillation in a high vacuum gave 15.7 parts (53%yield) of bis(1,2,2-trichloroethyl) sulfide as a yellow oil B.P. 110 C.,11 1.5736 having the same basic infrared spectrum as the product ofExample 1. The procedure of Example 2 gave higher yields, e.g., 47 to74.0% over several different runs, than that of Example 1. However, theproducts of Example 2, on the average, were not as pure as those ofExample 1.

EXAMPLE 3 Into a suspension of 1 part of ferric chloride in 30 parts ofcis 1,2-dichloroethylene there were added dropwise with stirring 12parts (0.06 mole) of 1,2,2-trichloroethyl sulfenyl chloride at 60 C.(moderate reflux) over a period of 15 minutes. Standing overnight,removing ferric chloride by using acetone and water, drying of theremaining solution and removing the organic solvent in vacuum gave 16.3parts of crude product which, in turn, furnished 7.6 parts (42.5% yield)of pure bis(1,2,2-trichloroethyl) sulfide as a yellow oil, B.P. 125 C.,n 1.5710 when subjected to fractionation in high vacuum.

EXAMPLE 4 3.1 grams (0.01 mole) of bis(1,2,2-trichloroethyl) sulfoxide(prepared in Example 6) were taken up in a mixture of 20 ml. of glacialacetic acid and 20 ml. of acetic anhydride and reduced by dropwiseaddition under stirring of 15 ml. of a 20% TiCl solution in concentratedhydrochloric acid at room temperature with occasional cooling to controlthe exothermic temperature rise over a period of 30 minutes. The mixturewas then kept for 3 hours at 90 to 95 C. and allowed to stand overnightat room temperature. All operations were carried out in a nitrogenatmosphere. Filtering 01f the formed precipitate of titanium dioxide andoxychlorides, diluting the filtrate with 2 volumes of water, taking upthe heavy oil into chloroform, repeated washing free of acid with water,drying and stripping of the solvent gave 2.8 grams (94% yield) of crudebis(1,2,2-trichloroethyl) sulfide, most of which distilled at 90 to 95C. at 0.05 mm. Hg and hav ing the same basic infrared spectrum as theproduct of Example 1.

EXAMPLE 5 Into 100 parts of a crude mixture of bis(1,2,2-trichloroethyl)sulfide and bis(1,2,2-trichloroethyl) disulfide made as in Example 1there were introduced under stirring and occasional cooling by means ofan external icewater bath at 30 C. over a period of 1 hour 15 parts ofdry chlorine gas, sufiicient to convert the 70% disulfide in the crudemixture to easily distillable 1,2,2-trichloroethyl sulfenyl chloride.The resulting mixture was then subjected to flash evaporation at 0.1 mm.Hg. The sulfenyl chloride which came over at 30 to 40 C. was recoveredby trapping and the residue distilled in a high vacuum to give 17 partsof bis(1,2,2-trichloroethyl) sulfide as a yellow oil in a yield of 57%.In other runs yields up to 63% were obtained.

EXAMPLE 6 62 grams (0.209 mole) of redistilled bis(1,2,2-trichloroethyl)sulfide were oxidized by diluting with 100 ml. of glacial acetic acidand gradually mixing with 23.7 grams of 30% aqueous hydrogen peroxide (aslight excess) followed by standing at room temperature (25 C.) over aperiod of 42 hours, followed by heating at 60 to 70 C. for a further 2hours. Diluting with 2 volumes of water, taking up the precipitated oilinto chloroform, removing free acetic acid by repeated washing withwater, drying and stripping of the solvent furnished a yield of 55 grams(84% yield) of a heavy oil which, on diluting with petroleum ether(Skelly B) and repeated cooling, gave 21 grams (32% yield) of crudesolid product which was recrystallized to give 17 grams (26% yield) ofpure white crystals of bis(1,2,2-trichloroethyl) sulfoxide, M.P. 88 C.,B.P. 102 to 105 (1., Cl 67.0% (68.0% theory); S 10.0% (theory 10.2% Thepure solid product is identified hereinafter as Compound 4922.

In a repeat of this experiment using a 4 day standing period at roomtemperature for the oxidation the yield of pure product was increased to34%. Low temperatures were also found to diminish the formation ofunsaturated materials as impurities.

EXAMPLE 7 60 grams (0.202 mole) of pure bis(l,2,2-trichloroethyl)sulfide were diluted with 150 ml. of glacial acetic acid, 20.2 grams of30% aqueous hydrogen peroxide were added and the mixture allowed tostand for 4 days at room temperature (25 to 27 C.). The mixture waspoured into 2 volumes of ice-water, the bottom oil taken up withchloroform and this solution treated as described in Example 6 to give63.5 grams (quantitative yield) of crude oil, from which after removalof the solid bis(1,2,2- trichloroethyl) sulfoxide by chilling from thepetroleum ether (Skelly B) and vacuum stripping gave 34.2 grams (54%yield) of bis(1,2,2-trichloroethyl) sulfoxide-oil form (i.e., theoil-modification). This was subjected to high vacuum distillation andboiled 117 to 125 C. at 0.02 to 0.03 mm. Hg and had an 11 1.5602 to1.5720. About 10 grams of the last fraction obtained in this range hadan 11 1.5720 and was a thick, almost colorless syrup. The oil productwas thus divided into two fractions. The lower boiling fraction in the117 to 125 C. range analyzed Cl, 66.3%, S, 10.6% and the higher boilingfraction in the 117 to 125 C. range analyzed Cl, 66.8%, S, 11.6%.(Theory for bis(1,2,2-trich1oroethyl)sulfoxide is Cl, 680%, S, 10.2%).The infrared spectrum for the high boiling oil fraction in Example 7 wasvery similar to that of the solid product of Example 6 both showingpeaks at 3.4 microns, 7.8 microns, 9.3 microns, 9.8 microns, 12.6microns and 13.7 microns. The spectrum for the solid product of Example6 showed a trace of unsaturated impurity at 10.9 microns while thespectrum of the oil of Example 7 showed considerably more unsaturatedimpurity at 10.9 microns and also showed unsaturated impurities at 6.4microns. The high boiling fraction in Example 7 was redistilled and hada B.P. to 117 C. This oil-modification of bis(1,2,2-trichloroethyl)sulfoxide is identified hereinafter as Compound 5008.

Crystallization of the oil-modification of bis(1,2,2-trichloroethyl)sulfoxide prepared in Example7 could not be achieved in this experimentor in a repeat experiment in which 51% yield of the oil-modification wasobtained.

EXAMPLE 8 10 grams of ferric chloride (anhydrous) were suspended in 400grams (100% excess) of vinylidene chloride and 102 grams (1.0 mole) ofsulfur dichloride were added dropwise under stirring and occasionalcooling to maintain a gentle reflux (35 C.) over a period of 1 hour.Standing overnight, heating to reflux for 3 hours, removing ferricchloride by treatment with acetone, drying and stripping 01f excessvinylidene chloride gave 232 grams of crude bis(2,2,2-trichloroethyl)sulfide-bis(2,2,2-trichloroethyl) disulfide mixture which was subjectedto fractionation. A 30% yield was obtained of a colorless fraction whichhad a HE 91 0., u 1.5642- This 3.5 grams (0.0118 mole) ofbis(2,2,2-trichloroethyl) sulfide were diluted with 10 ml. of glacialacetic acid and 1.2 grams of 31.0% aqueous hydrogen peroxide (0.01) moleadded. The mixture was allowed to stand for 6 days at room temperature(25 to 30 C.) and diluted with water to give 3.7 grams (quantitativeyield) of the crude product as a white solid. The latter was taken up inchloroform, washed several times with water, dried and stripped to give1.8 grams (50% yield) of bis(2,2,2- trichloroethyl) sulfoxide (Compound5025) as a white solid which on recrystallization had a M.P. of 135 to137 C. and had a B.P. of 143 to 144 C.

EXAMPLE 10 29.7 grams (0.1 mole) of bis(1,2,2-trichloroethyl) sulfidewere diluted with 100 ml. of petroleum ether (Skelly B) anddehydrochlorinated by dropwise addition with stirring and occasionalcooling of 20.3 grams (0.2 mole) of triethyl amine in Skelly B (1:1 byvolume). Continued stirring at room temperature for 4 hours, removingthe triethylamine hydrochloride formed and the unreacted triethylamineby washing with dilute aqueous hydrochloric acid and then with diluteaqueous sodium bicarbonate, followed by drying and stripping otf thesolvent gave 24 grams (quantitative yield) of crude residue which ondistillation gave 20.5 grams (85% yield) of1,2-dichlorovinyl-1,2,2-trichloroethyl sulfide (Compound 4968) as ayellow oil B.P. 53 to 54 C., n 1.5715 which analyzed CI, 66.6% (theory68.2%), S, 11.7% (theory EXAMPLE 11 10 grams (0.0336 mole) ofbis(1,2,2-trichloroethyl) sulfide were dissolved in 50 ml. of anhydrousbenzene and a solution of 1.55 grams of sodium metal (2 gramequivalents) in 100 ml. of anhydrous ethyl alcohol was added dropwisewith stirring at 20 to 25 C. with occasional cooling. Thedehydrochlorination proceeded rapidly and the sodium chloride formed inquantitative amount was filtered off after the reaction mixture wasstirred for 1 hour at room temperature (25 to 30 C.). Removal of all thesolvents gave 7.3 grams (97% yield) of crude bis(l,2-dichlorovinyl)sulfide as a yellow oil which, after distillation, gave 5.5 grams (73%yield) of pure bis(l,2- dichlorovinyl) sulfide (Compound 5021) as ayellow oil B.P. 40 to 43 C., 11 1.5803.

EXAMPLE 12 grams (0.0208 mole) of recrystallized bis( 1,2-dichlorovinyl)sulfoxide prepared according to Example 13 were dissolved in a mixtureof 20 ml. of glacial acetic acid and 25 ml. of acetic anhydride andreduced by dropwise addition with stirring of 30 ml. of a 20% solutionof TiCl in concentrated hydrochloric acid. The mixture was kept for 4hours at 95 to 100 C. All of the operations were carried out in anitrogen atmosphere. The titanium oxide and oxychlorides formed werefiltered ofi, the filtrate was diluted with 2 volumes of water, and theoil taken up in chloroform, repeatedly washed with water until free ofacid, dried and stripped of solvent to give 2.5 grams (54% yield) ofbis(l,2-dichlorovinyl) sulfide as a yellow oil B.P. 40 to 41 C., n1.5826.

EXAMPLE 13 12 grams (0.0383 mole) of pure bis(1,2,2-trichloroethyl)sulfoxide were dissolved in 100 ml. of dry benzene anddehydrochlorinated by dropwise addition with stirring and cooling atbetween 4 and C. of a solution of 7.75 grams (0.0766 mole) oftriethylamine in 50 ml. of dry benzene over a period of 1 hour. Themixture was allowed to warm to room temperature with continued agitationover a period of 1 further hour, the triethyl amine hydrochloride formedwas removed, the product washed first with dilute hydrochloric acid andthen with wateruntil neutral, dried and the benzene removed in vacuum togive 8.1 grams (88.2% yield) of crude product which was distilled togive 7 grams (76% yield) of his- (l,2-dichlorovinyl) sulfoxide (Compound4965) as a colorless oil B.P.0 017 69 to 70 C., n 1.5865. The oilsolidified on standing. It was recrystallized from Skelly B to give 5.3grams (57.5% yield) of pure Compound 4965, M.P. 58 C. Analysis gave forC1, 57.5% (theory 59.2%) and for S, 13.2% (theory 13.4%).

EXAMPLE 14 1.5 grams (0.0067 mole) of bis(l,2-dichlorovinyl) sulfidewere diluted with 15 ml. of glacial acetic acid and mixed with 0.76 gramof 30% aqueous hydrogen peroxide. The reaction mixture was allowed tostand at room temperature (25 to 27 C.) for two days, poured into waterand small amounts of acetic acid and water were removed from the bottomoil obtained to give 1.6 grams (quantitative yield) of a colorless oilwhich solidified on standing. The product was bis(l,2-dichlorovinyl)sulfoxide. It had the same infrared spectrum as the product of Example13.

EXAMPLE 15 13.0 grams (0.05 mole) of1,2-dichlorovinyl-1,2,2-trichloroethyl sulfide were diluted with 30 ml.of glacial acetic acid and slowly mixed with 5.9 ml. of a 30% aqueoushydrogen peroxide solution and allowed to stand at room temperature for48 hours. The oxidation was completed by heating for 45 minutes at C.The mixture was poured into two volumes of water, the bottom oil takenup in chloroform, washed free of acetic acid with water, dried andstripped to give 12.7 grams (92% yield) of crude product which wasdistilled to give 9.5 grams of pure1,2-dichlorovinyl-1,2,2-trichloroethyl sulfoxide (Compound 5009) B.P. 87to 89 C., n 1.5765. Elemental analysis gave for C1, 62.9% (theory,64.1%) and for S, 10.9% (theory, 11.6%).

EXAMPLE 16 10 grams (0.032 mole) of pure bis(2,2,2-trichloroethyl)sulfoxide made according to Example 9 were dissolved in a mixture of 25ml. of acetic acid and 35 ml. of acetic anhydride. Then, 40 ml. of a 20%TiCl solution in concentrated hydrochloric acid were added with careunder stirring and cooling. Finally, the temperature was allowed to goup to to C. and kept there for 6 hours. The process was carried out in anitrogen atmosphere. The product was then purified in the manner.described in Example 4 and distilled to give 5 grams (53%) of bis-(2,2,2-trichloroethyl) sulfide B.P. 88 to 89 C n 1.5551.

EXAMPLE 17 To 60 grams of bis(2,2,2-trichloroethyl) sulfide-bis-(2,2,2-trichloroethyl) disulfide mixture (0.2 molar as the sulfide)diluted with 100 ml. of glacial acetic acid there were added 52.3 gramsof a 26% aqueous hydrogen peroxide solution (0.4 mole) at 90 to 105 C.over a period of 1 hour with stirring. The mixture was heated furtherfor 1 hour at 93 C. and then allowed to stand overnight at roomtemperature to complete the oxidation. The mixture was diluted with 2volumes of water, filtered, washed free of acids, taken up inchloroform, dried and stripped to give 15 g. (24% yield) of crude solidwhich was recrystallized from Skelly B to give 13 grams (21% yield) ofpure bis(2,2,2-trichloroethyl) sulfoxide, M.P. 136 to 137 C. (Compound5025). Elemental analysis gave for Cl, 66.6% (theory, 68.0%) and for S,9.9% (theory, 10.2%).

7 EXAMPLE 18 To 6.0 grams (0.025 mole) of bis(2,2-dichlorovinyl)sulfoxide (Compound 5026) diluted with a mixture of 15 ml. of glacialacetic acid and 35 ml. of acetic anhydride there were added dropwisewith stirring 30 grams (0.05 mole) of a 20% TiClg solution inconcentrated hydrochloric acid while cooling under a blanket of nitrogengas. The temperature was allowed to rise slowly to 100 to 105 C. by theend of the addition period. The mixture was kept at this temperature for3 hours and then worked up and the crude product isolated in the mannerdescribed in Example 4. The product was distilled in a high vacuum togive 4.0 grams (77% yield) of pure bis(2,2-dichlorovinyl) sulfide(Compound 5027), B.P. 59 to 60 C., 11 1.5955. Elemental analysis gavefor CI, 61.7% (theory, 63.3%) and for S, 14.3% (theory, 14.1%).

EXAMPLE 19 grams (0.0336 mole) of bis(2,2,2-trichloroethyl) sulfide weredissolved in 50 ml. of anhydrous benzene and dehydrochlorinated bydropwise addition with stirring and occasional cooling of 100 m1. ofanhydrous ethyl alcohol containing 1.55 grams (2 gram equivalents) ofsodium metal at to C. The mixture was allowed to stand at roomtemperature for 5 to 6 hours, the sodium chloride formed filtered off,the product washed with water, extracted with chloroform, dried and thesolvents removed by distillation to give 3.0 grams (40% yield) of purebis(2,2-dichlorovinyl) sulfide, B.P. 47 'C., 11 1.5872.

EXAMPLE 20 6.5 grams (0.0219 mole) of bis(2,2,2-trichloroethyl) sulfide(Compound 5006) were diluted with 25 ml. of benzene anddehydrochlorinated by dropwise addition of 4.43 grams (0.0428 mole) oftriethylamine. Standing overnight at room temperature (25 to C.)followed by refluxing for 2 hours, removing the triethylaminehydrochloride and unreacted triethylamine by filtration and washing withdilute aqueous hydrochloric acid and water gave 3.5 grams of a yellowoil, most of which distilled at B.P. 51 to 52 C. and which was a mixtureof a large proportion of 2,2-dichlorovinyl-2,2,2-trichloroethyl sulfide(Compound 5103) with some -bis(2,2-dichlorovinyl) sulfide and somestarting Compound 5006.

EXAMPLE 21 The amount of triethylamine was reduced to only 1 moleequivalent in this example wherein 10 grams (0.0337 mole) ofbis(2,2,2-trichloroethyl) sulfide (Compound 5006) were diluted with 50ml. of Skelly B and 3.4 grams (0.0337 mole) of triethylamine were addeddropwise with stirring at 10 to 15 C. The temperature was allowed torise to room temperature, followed by refluxing at 55 C. for 3 hours tocomplete the reaction. Washing the resulting Skelly B solution withdilute aqueous hydrochloric acid, sodium bicarbonate and water, followedby drying and stripping and distillation in high vacuum gave 5.4 gramsof a pale orange oil, B.P. 70 to 73 C., n 1.5575. Infrared analysis andgas chromatography showed that the product was a mixture of2,2-dichlorovinyl-2,2,2- trichloroethyl sulfide (Compound 5103),bis(2,2-dichlorovinyl) sulfide (Compound 5027) and the starting Compound5006.

Compound 5103 was isolated in pure form by separating from a gaschromatrographic column of a sample obtained by using ethyl alcohol asthe solvent during dehydrochlorination.

Example 21 was repeated by replacing the Skelly B in turn by benzene,tetrahydrofurane and ethyl alcohol and a similar mixture of productobtained. The general method was to dissolve 10 grams (0.03 mole) ofCompound 5006 in 50 ml. of benzene (or tetrahydrofurane, or ethylalcohol), heating to beginning reflux and adding slowly 3.7 grams (1.1mole equivalent) of triethylamine over '30 minutes, washing the benzenemixture with water, taking up the oil in chloroform, drying andstripping to give crude oils which were separated into their componentsby gas chromatography.

Thus, the results using (bis(2,2,2-trichloroethyl) sulfide (Compound5006) using triethylamine as the dehydrochlorination agent are difierentfrom those using bis(1,2,2- trichloroethyl) sulfide (Compound 4975.Compound 4975, even with a considerable excess of triethylamine gave thehemiunsaturated Compound 4968 exclusively, whereas Compound 5006 gavemixtures of herniunsaturated Compound S 103 and considerable amounts ofthe fully unsaturated Compound 5027.

EXAMPLE 22 13.0 grams (0.0415 mole) of bis(2,2,2-trichloroethyl)sulfoxide were dissolved in 75 ml. of dry benzene and dehydrochlorinated by dropwise addition of 8.4 grams (0.083 mole) oftriethylamine with stirring and cooling at 10 to 15 C. for 30 minutes.The mixture was allowed to warm to room temperature (25 to 30 C.), thetriethylamine hydrochloride forrned removed by filtration, the productwashed with water, dried and the benzene filtrate stripped to give 9.0grams yield) of bis(2,2-dichlorovinyl) sulfoxide (Compound 5026) afterchilling of a Skelly B solution of the crude material from the benzenesolution. Compound 5026 was a white crystalline solid, M.P. 35 to 36 C.

EXAMPLE 23 10 grams of anhydrous ferric chloride were dispersed in 786grams (6.0 mole) of trichloroethylene, the mixture warmed to 70 to 75 C.and 206 grams (2.0 moles) of sulfur dichloride added at this temperaturedropwise with stirring over a period of 1 hour. The mixture was heatedfor an additional 3 hours at 70 to 75 C. and the ferric chloride removedby filtration, followed by decanting with acetone, drying and strippingto give 526 grams of a mixture of bis(1,2,2-tetrachloroethyl) sulfideand his (1,2,2,2-tetrachloroethyl) disulfide as a dark oil. This darkoil mixture is identified hereinafter as Compound 4501.

A 102 gram portion of this product was fractionated to give 20 grams ofpur bis(l,2,2,2-tetrachloroethyl) sulfide (Compound 5052), B.P. 74 to 75C., 11 1.5834.

EXAMPLE 24 10 grams (0.0273 mole) of Compound 5052 were dissolved in 50ml. of glacial acetic acid and 3.1 grams of 30% aqueous hydrogenperoxide added at room temperature. The oxidation mixture was allowed tostand for 2 weeks, followed by heating at 90 to C. for 3 hours. Themixture was poured into 1 volume of water, the bottom oil freed ofacetic acid by successive water washings, diluted with chloroform anddried over anhydrous magnesium sulfate, and the solvent stripped to give7.1 grams (70% yield) of bis(1,2,2,2-tetrachloroethyl) sulfoxide(Compound 5054) 11 1.5830.

EXAMPLE 25 15 grams (0.0408 mole) of bis(1,2,2,2-tetrachloroethyl)sulfide were dissolved in 50 ml. of dry benzene and dehydrochlorinatedby dropwise addition at 30 to 35 C. with stirring and cooling of 4.12grams (0.0816 mole) of triethylamine in 10 ml. of benzene. Stirring ofthe mixture at room temperature for 3 hours followed by standing for 48hours completed the reaction. Filtration and water washing to remove allthe triethylamine hydrochloride, drying and stripping of the benzenesolution gave 12.5 grams of crude residue which furnished 10.0 grams(83.5% yield) of bis(perchlorovinyl) sulfide (Compound 5053) as a yellowoil, B.P. 71 to 73 C., n 1.5985.

EXAMPLE 26 To 5 grams (0.0162 mole) of bis(perchlorovinyl)sulfoxidediluted with 15 m1. of acetic acid and 35 ml. of acetic anhydride therewere added dropwise 20 grams (0.032 mole) of a solution of 20% TiCl inconcentrated hydrochloric acid with stirring and cooling in a nitrogenatmosphere. The temperature was allowed to gradually climb to 100 to 105C. at the end of the addition period. The mixture was heated at 100 to105 C. for a further 3 hours to complete the reduction. The precipitateof titanium oxide and oxychlorides was filtered off, the filtratediluted with 2 volumes of water, taken up in chloroform, washedrepeatedly with water to remove the acid, dried and stripped of solventto obtain 3.5 grams of bis(perchlorovinyl)sulfide.

EXAMPLE 27 13 grams (0.034 mole) of Compound 5054 were dissolved in 100ml. of dry benzene and dehydrochlorinated by dropwise addition of 6.9grams (0.068 mole) of triethylamine diluted with 20 ml. of benzene withstirring at 30 to 35 C. over a period of 20 minutes. Further heating for1 hour at 50 to 60 C., removing the triethylamine hydrochloride byfiltration and washing with diluted aqueous hydrochloric acid, dryingover anhydrous magnesium sulfate gave 10.5 grams (a quantitative yield)of crude product which was found to contain 78% of bis (perchlorovinyl)sulfoxide (Compound 5055), an oil which, on distillation in high vacuum,had a B.P. 95 to 100 C., n 1.6070.

EXAMPLE 28 5 grams (0.0169 mole) of bis(perchlorovinyl) sulfide weretaken up in 20 ml. of glacial acetic acid and 2.0 grams of 30% aqueoushydrogen peroxide solution were added at room temperature. This mixturewas allowed to stand for 14 days, poured into 2 volumes of water, thebottom oil taken up in chloroform, washed repeatedly with water toremove acetic acid, dried and stripped to give 4.6 grams (87% yield) ofcrude bis(perchlorovinyl) sulfoxide n 1.6024, C1, 67.8% (theory, 68.9%)S, 10.6% (theory, 10.4%

EXAMPLE 29 Even when the amount of peroxide was doubled it was notpossible to form the sulfone from Compound 5053 but, instead, thesulfoxide (Compound 5055) was obtained, as shown in this example.

1.5 grams (0.00512 mole) of bis(perchlorovinyl)sulfide were taken up in15 ml. of glacial acetic acid, 1.10 grams (0.0102 mole) of 30% aqueoushydrogen peroxide added and the mixture heated on a steam bath for 3hours. After standing for several days at room temperature, it wasworked up by pouring into water, the lower oil layer taken up inchloroform, the small amount of acetic acid removed by repeated washingwith water, the product dried and stripped to give 1.3 grams (82% yield)of pure bis(perchlorovinyl) sulfoxide as a colorless oil.

The compounds of the present invention can be used alone as nematocidesor fungicides, but it has been found desirable to apply them to thepest, e.g., to the soil habitat of nematodes, together with inert solidsto form dusts, or more preferably suspended in a suitable liquiddiluent, preferably water. There can also be added surface active agentsand inert solids in such liquid formulations. Desirably, 0.05 to 1% byweight of surface active agent is employed. The active ingredient can befrom 0.01 to 95% by weight of the entire composition in such cases.

In place of water there can be employed organic solvents as carriers,e.g., hydrocarbons such as benzene, tolu- 10 ene, xylene, kerosene,diesel oil, fuel oil, and petroleum naphtha, ketones such as acetone,methyl ethyl ketone and cyclohexanone, and alcohols, e.g., ethanol,isopropanol and amyl alcohol, etc.

The nematocides and fungicides of the present invention can also beapplied with inert nematocidal or fungicidal adjuvants or carriers suchas talc, pyrophyllite, synthetic fine silica, Attaclay, kieselguhr,chalk, diatomaceous earth, lime, calcium carbonate, bentonite, fullersearth, cottonseed hulls, wheat flour, soybean flour, pumice, tripoli,wood flour, walnut shell flour, reduced flour and lignin.

It is frequently desirable to incorporate a surface active agent in thepesticidal compositions of this invention. Such surface active agents,i.e., wetting agent, are advantageously employed in both the solid andliquid compositions. The surface active agent can be anionic, cationicor nonionic in character.

Typical classes of surface active agents include alkyl sulfonate salts,alkylaryl sulfonate salts, alkyl sulfate salts, alkylamide sulfonatesalts, alkylaryl polyether alcohols, fatty acid esters of polyhydricalcohols and the alkylene oxide addition products of such esters, andaddition products of long chain mercaptans and alkylene oxides. Typicalexamples of such surface active agents include the sodium alkyl benzenesulfonates having 14 to 18 carbon atoms in the alkyl group,alkylphenol-ethylene oxide condensation products, e.g., p-isooctylphenolcondensed with 10 ethylene oxide units, soaps, e.g., sodium stearate andpotassium oleate, sodium salt of propylnaphthalene sulfonic acid,(di-2-ethyl hexyl) ester of sodium sulfosuccinic acid, sodium laurylsulfate, sodium salt of the sulfonated monoglyceride of cocoanut fattyacids, sorbitan sesquioleate, lauryl trimethyl ammonium chloride,octadecyl trimethyl ammonium chloride, polyethylene glycol lauryl ether,polyethylene esters of fatty acids and resin acids, e.g., Ethofat 7 and13, sodium N- methyl-N-oleyltaurate, Turkey Red Oil, sodiumdibutylnaphthalene sulfonate, sodium lignin sulfonate (Marasperse N),polyethylene glycol stearate, sodium dodecylbenzene sulfonate, tertiarydodecyl polyethylene glycol thioether (Nonionic 218), long chainethylene oxide propylene oxide condensation products, e.g., Pluronic 61,sorbitan monolaurate, polyethylene glycol ester of tall oil acids,sodium acetylphenoxyethoxyethyl sulfate, tris (polyoxyethylene) sorbitanmonostearate (Tween 60), sodium dihexyl sulfosuccinate.

The solid and liquid formulations can be prepared by any of theconventional methods. Thus, the active ingredient can be mixed with thesolid carrier in finely divided form in amounts small enough to preservethe free-flowing property of the final dust composition.

In commercial practice the compositions containing the nematocides ofthe present invention are applied to the soil infested with nematodes.

In the following examples or tables illustrating nematocidal orfungicidal activity the compounds of the invention, as well as thecomparison compounds, were formulated as wettable powders consisting of50% of the compound being tested, 46% Hi-Sil 233 (ultra fine silica), 2%Maresperse N (sodium lignin sulfonate) and 2% Pluronic (polyethyleneoxide-propylene oxide adduct molecular weight about 1000). This wettablepowder is hereinafter designated as Formulation A.

EXAMPLE 30 The saprophytic nematode tests (NESA) were carried out inwater as the medium with Panagrellus and Rhabditis spp. nematodes atroom temperature utilizing Formulation A. The results are recorded inTable I as percent kill at the indicated dosages in parts per millionafter a 4 day incubation period. A 10% kill is merely the same amount ofkill as occurs with a blank sample.

It will be observed that the unsaturated sulfoxide Compound 5055(perchlorovinyl sulfoxide) was an excellent nematocide whereas thecorresponding sulfide (Compound 5053) was completely ineffective. Bothbis(1,2,2,2- tetrachloroethyl) sulfide (Compound 5052) and thecorresponding sulfoxide (Compound 5054) were also ineffective asnematocides. In contrast, bis(l,2,2-trichloro ethyl) sulfide (Compound4975) and the corresponding sulfoxide (Compounds 4922 and 5003) wereexcellent nematocides. Bis(1,2-dichlorovinyl) sulfide (Compound 5021)was a good nematocide and the corresponding sulfoxide (Compound 4965)was even better. This was also true of the mixed saturated-unsaturatedsulfide Compound 4968 and the corresponding sulfoxide (Compound 5009').

The bis(2,2-dichlorovinyl) sulfide (Compound 5027) and sulfoxide(Compound 5026) were considerably inferior as nematocides to thecorresponding 1,2-dichlorovinyl isomers (Compounds 5021 and 4965).Surprisingly, in view of the other results bis(2,2,2-trichloroethyl)sulfide (Compound 5006) was a better nematocide than the correspondingsulfoxide (Compound 5025), although neither was among the bettercompounds tested.

EXAMPLE 31 Several of the compounds were also tested against parasiticnematodes employing Formulation A. The nematode employed was Meloidogynespp. and the procedure was a 10-day contact test carried out inwater-agar medium in the presence of tomato roots at room temperature.The results indicated high activities e.g. for Compounds 4975 and 4922,which were found to be 100% effective at 25 p.p.m. and 50% eifective at12.5 p.p.m. rates of application.

EXAMPLE 32 The compounds were also tested as fungicides in platefungicide tests as indicated in Table II. The compounds were made upinto Formulation A and then added to agar cultures of the fungi. In thetable 10 indicates 100% effectiveness and indicates no effectiveness. InTable 11 P stands for Pythium spp., R for Rhizoctonia, F for Fusariumand H for Helminthosporium. The concentrations are expressed as partsper million (p.p.m.).

TABLE II Compound at p.p.m.:

Compounds 4922, 5008, 4965 and 5009 were very effective as soilfungicides at the rate of (lbs/acre) of 200, 100, 50, 25 and 12.5.Compounds 5054 and 5055 were efiective soil fungicides at 200 and 50lbs/acre. Compound 4922 was the best of all the compounds as a soilfungicide.

Bis(1,2,2-trichloroethyl) sulfoxide and its use as a fungicide andnematocide are claimed in our copending application Ser. No. 338,297,filed Jan. 17, 1964, now U.S. Pat. 3,249,495.

We claim:

1. A process of killing pests which are nematodes or fungi comprisingapplying to said pests a pesticidally effective amount of eitherbis(dichlorovinyl) sulfide, bis- (trichloroethyl) sulfide, or 1,2dichlorovinyl-1,2,2-trichloroethyl sulfide.

2. A process according to claim 1 wherein the compound isbis(1,2,2-trichloroethyl) sulfide.

3. A process according to claim 1 wherein the compound isbis(2,2,2-trichloroethyl) sulfide.

4. A process according to claim 1 wherein the pests are fungi and thecompound is bis(trichloroethyl) sulfide.

5. A process according to claim 1 wherein the pests are nematodes andthe compound is bis(dichlorovinyl) sulfide.

6. A process of killing nematodes which comprises applying to saidnematodes a nematocidal amount of bis- (1,2-dichlorovinyl) sulfide.

7. A process of killing nematodes which comprises applying to saidnematodes a nematocidal amount of bis- (2,2dichlorovinyl) sulfide.

8. A process of killing nematodes which comprises applying to saidnematodes a nematocidal amount of 1,2-dichlorovinyl-l,2,2-trichloroethy1 sulfide.

References Cited FOREIGN PATENTS 627,096 7/1963 Belgium 424-337 JEROMED. GOLDBERG, Primary Examiner

